Art of agglomerating ores.



J. H. PAYNE.

ART 0; AGGLOMERATING OHES.

APPL'ICATION mu) JULY 28. 1915.

am m W M. M W m JAMES E. PAYNE, F BALTIMORE, MARYLAND.

ART OF AGGLOMERATING ORES.

application filed July 28, 1915. Serial Ito. 42,346.

To all whom it may concern:

Be it known that I, JAMES H, 1?AYNE, a citizen of the United States, residing at ave Baltimore, in the State of Maryland,

invented or discovered certain new 3 and useful Improvements in the Art of Agglomerating Ores, of which the following 1s a specification, reference being hadtherein tothe accompanying drawings.

The present HIVQDIIOIL relates to the ag glomeratlon of ores, concentrates, mattes and the like and has special reference tothe treatment of such materials containing large quantities of sulfur in the form of sulfids. The ores, mattes or concentrates treated may contain sulfids of copper, lead, zinc or other metals.

' Y M invention includes the retention within t e productof substantially the entire amount of the fixed sulfur, although when treating such sulfids as contain material amounts of pyrites, more or less, or even the whole of the feeble atom of sulfur may be driven off from the ore, during the heating ste 1 h my prior U. S. Patent No. 1,114,029, I have described and claimed a process of agglomerating sulfid ores and the like, which process-comprises as one of its distinctive features, the stepof heating the ore to be agglomerated by the action of a non-oxidizing flame which flame may be reducing or neutral. ,Said step is also included as one of the preferred features of the present invention, although obviously any other mode'of' heating, in which the ore while in a heated state is not brought into contact'with material amounts of free oxygen orair may be em loyed. i

s a preferred mode of execution of my process, I give the following example, which taken in connection with the accompanying drawing forming part of this specification, illustrates a preferred mode of execution of the invention.

The drawing shows a side elevation, partly in section of a preferred form of apparatus, although obviously various other forms of apparatus can be employed without departing from the spirit of my invention;

The ore to be agglomerated may be intro duced through the hopper 10, into the rotating inclinedfurnace 11, which in the caseof the sulfid ores above referred to, is preferably heated by a reducing or neutral Specification of Letters Patent.

Fatented May 2, 1916,

lower portion or "slack of the conveyer' passes through a tank 15, containing water or other suitable cooling liquid for the purpose of cooling the conveyer.

At l6'isprovided a Wiper or leveler, the function of which is to prevent too large a portion of the ore from being heaped up upon the successive pans of the conveyer.

At 17 are illustrated perforated pipes which may be employed for throwing sprays of water upon the ore carried by the conveyer and upon the conveyor itself, for the purpose of completely cooling the ore before the same drops into the car 18, or is otherwise discharged from the conveyer 13.

In order to prevent undue amounts of air fromentering the lower end of the rotating extends horizonthe undue amounts of air from being drawn into the furnace, oras a substitute for the means above referred, to. I can employ a damper 22 in the flue leading to the stack, which will obstruct the draft and hence prevent the suckin in of undue amounts of air at the lower en "of the furnace.

, The ore in passing through the furnace is heated to the point of incipient fusion, which will, of course, rieties of sulfid ore, concentrates. or mattes. By reason of the non-oxidizing atmosphere, the melting point of the ore, which is lower the higher the sulfur content of the ore, is materially lowered by the enforced retention of sulfur, hence the amount of fuel necessary to bring the ore to the point of in-/ vary fordifierent vathe ore, the agglomerated ore is particularly suited for blast furnace food, because it has an excess of sulfur, which can be made to act as fuel, by the well known methods of pyritic smelting, thus replacing at least a portion of the coke ordinarily necessary in commercial blast furnace smelt- A up into Instead of rolling the semi-fused ore into masses of considerable size which operat on requires large quantities of fuel and which also is open to the objection of fouling the furnace by the production of slag, I cause the ore to drop as soon as kiln to the horizontally moving conveyer and to spread itself thereon, by the motion of the conveyer, aided by the spreading de: vice 16 above referred to, in a relatively thin layer. structed of metal and is preferably previously cooled, so that the semi-fused ore becomes w chilled and after traveling a short distance on this conveyer, is sufficiently cool to be dumped into a car or other suitable receptacle or conveying means. During the stage of incipient fusion within the lower end of the furnace 11, the ore may roll itself masses of appreciable size, which may be, in the process of mypre'sent invention, as small as grains of wheat or larger. This material is then dropped onto the traveling conveyer and is spread out in the form of a slab which maybe about two inches thick, which when somewhat cooled possesses a beautifully honey-combed structureconsisting of individual aggregates or particles, bonded together by the freezing of the partially melted aggregates While in the state of quiescence, this result being secured also in part by the use of the cold metal of the bed of the traveling conveyer. This product consists of an agglomerated sulfid,

,' containing if desired practically all the fixed sulfur of the original ore or concentrate.

As copper sulfid concentrates above referred to generally contain around 16% of fixed sulfur, a product containing this amount can readily be obtained by my process. The agglomerated ore or concentrate will thus consist essentially of metal sulfid.

So far as I am aware, no method of agglomeration heretofore in use has produced a product containing such large amounts of sulfur, since in all the agglomerating methods heretofore in use, the step of roasting is employed, the result of which is to mate cooling is preferably not produced by the rially lower the sulfur content. In my process no roasting whatever need occur. The

action of cold air upon the hot sulfid ore,

since such a step would produce a consider.-

able amount of roasting and hence lower the sulfur content, and would also add to the production of slag, A considerable portion of the heat in the ore will be removed by being absorbed by the cold metal of the conveyer, and after such chilling operation,

either watenor air can safely be used, m'nce it has uniformly.v reached incipient fusion, directly from the .The conveyor is preferably, con- I y as mattes, I desire 'at the reduced temperatures no roasting of the ore will be produced, either by cold air or by water. After being dropped onto the conveyer, the ore" may travel for a distance of about 20 feet, before being dumped into the car 18. y

I am aware that it has heretofore been proposed to agglomerate sulfid ores, without previously roasting, and without roasting during the aggregating step, by the addition tothe fine ore of a suitable binder. In my process, however, I do not add a binder, other than the semi-fused ore itself. While I have particularly described my process as applied to the treatment of sulfid ores, or other sulfid-bearing material, such to state that the idea of partially fusing amass of ore, for example by heating the same in a rotating furnace 11, and thereafter spreading out the mass of material in the traveling molds 1 3, and cooling the same therein to form a sintered honey-combed mass, is applicable also to the treatment of other ores, concentrates and 'the like, and I do not desireto limit myself .peratureof incipient fusion, under conditions to prevent removal of material amounts of the fixed atom of sulfur, spreading out the heated ore, and cooling the same to below a roasting temperature, in the substantial absence of free oxygen.

2. In the agglomeration of sulfid ores, mattes, and concentrates, the steps of heating under non-roasting conditions to incipient fusion, spreading out the heatedmaterial under non-roasting conditions, and cooling under non-roasting conditions.

3. A process of agglomerating metal sulfids which comprises heating said sulfids, under non-roasting conditions, to-a temperature at which at least a portion of the ore becomes fused, molding said material and freezing the partially melted particles while in a state of quiescenca' 4. A process of agglomerating metal sulfids which comprises' heating the same to incipient fusion, placing the'hot mass in a cooled mold, and allowing the fused particles to solidify therein.

5. In a process of agglomerating fine metal-bearing material which comprises heating the same to incipient fusion, spreading out the hot material in a cooled mold in the form of a relatively thin layer, and allowing the' same to cool and set while in a state of quiescence.

In testimony whereof I aifix my si ature.

" JAMES H. PA E. 

